Lesson Summary
• Plastic pipes have replaced metal pipes and fittings, and are widely used in the plumbing trade today.

• Plastic is chemically inert, resistant to corrosion, and requires no soldering or welding.

• Thermoplastic and thermosetting are the two general categories of plastic. While the former can be repeatedly softened by heating and hardened by cooling, the latter undergoes permanent chemical change when heated.

• ABS, PVC, CPVC, PE, PEX, and PB are the six types of plastic pipes that plumbers work with.